APR Catback Exhaust System w/ Center Muffler For Audi S6 & S7 4.0 TFSI (C7/C7.5)

The APR Catback Exhaust System personalizes your vehicle’s looks, sound and performance. Beautifully hand-crafted T304-stainless-steel components adorn the system with stunning TIG-welding throughout. Our straight-through brushed-finished mufflers smooth the exhaust note to a deep growl, without adding restrictions. Strong high-quality bracketry and OEM-style clamps hold the system steadily in place, making the install or removal a snap, and fitment simple, yet precise. Cast 2.75” to dual 2.5” rear splitter creates an ultra-smooth transition, steadily feeding exhaust gasses out of the system. Our cast valve housings enable the vehicle to be fitted with the factory electronic valve actuators, retaining OEM valve operation.  Finally, removable 4" polished slash-cut exhaust tips finish the system, adding a classy motorsport-inspired touch to the rear of the vehicle. Optional tip upgrades, and an optional center muffler / Center muffler delete is available.  

Quick Facts

• T304 stainless-steel construction
• Argon-back-purged TIG welding throughout
• Dual 2.75" to quad 2.5" mandrel-bent brushed tubing
• Ultra-smooth cast 2.75" to dual 2.5" splitters
• Brushed-finished straight-through sound-absorption mufflers with an optional center muffler or straight pipes
• Polished 4" slash-cut exhaust tips (removable and upgradable)
• Cast valve housings and brackets for OEM electronic actuators
• Rugged and precise mounting brackets
• CNC bent and laser cut tunnel brace for added chassis rigidity
• OEM style slip clamps and Torca AccuSeal T304 tip clamps
• Direct fit to the OEM and APR Race DP exhaust systems
• Low-profile design, suitable for lowered vehicles
• Larger diameter piping compared to stock
• Larger diameter tips compared to stock
• Designed, developed, assembled and quality controlled in-house
• Easy to install
• Limited lifetime warranty

System Overview

Our exhaust system uses larger piping compared to the factory exhaust system, yet weighs less in the base configuration. We use dual 2.75" OD piping, which then splits to a quad 2.5" design. The factory system uses 2.375" piping. Finally, our system’s 4" exhaust tips dwarf the factory tips, giving the rear of the vehicle a sportier look. The system shown below includes the optional center muffler.

APR Also offers a complete system without a center muffler for a louder, slightly more aggressive exhaust. 

CBK0009 - APR Catback Exhaust System For Audi S6 & S7 4.0 TFSI (C7/C7.5)

Component Details

Mufflers

The mufflers are responsible for reducing the exhaust note and do so without adding unnecessary restrictions to the system. Each unit features two straight-through perforated tubes that are tightly wrapped with stainless steel and fiberglass material. With the valves closed, the system is tamer, but once opened, the system sounds deep, throaty and aggressive! The mufflers have a beautiful brushed finish, and are tucked high in the exhaust tunnel, making them perfect for lowered vehicles and a treat to see when looking at the vehicle from the rear. The optional front muffler is responsible for reducing sound volume further. This configuration is recommended for customers who have our Race DPs and want a tamer exhaust note.

Cast Splitter

We cast the rear muffler splitters to maximize the system’s performance by keeping exhaust velocity high and back pressure low. This is accomplished by gradually splitting the system from a single 2.75” pipe to dual 2.5” pipes. The organically shaped casting allows us to make this transition gradually as to not disturb the flow of gasses.

Exhaust Valves

Our system features two valves that allow control of the volume of the system via the factory exhaust valve actuators. In doing so, the system can go from tame to aggressive instantly! Unlike pneumatic systems, and other common valves found in the market today, our system maintains identical OEM operation all the way down to the factory valve actuation angles. Furthermore, the system is compatible with aftermarket exhaust remotes, allowing end users to manually open the system at the click of a button.

We cast the valve housings out of T304 stainless steel. Internally the system uses CNC-machined T303 components and brass bushings, which have stood up to our extreme torture testing. All necessary hardware is welded into place and is designed to combat heat and vibration for years to come.

Brackets

Our brackets ensure a strong and precise fit, every time. With our design, you’ll never need to worry about the brackets sagging and losing their shape over time, or the post slipping out of the hangers. The brackets are rigid, exact in their position, fit snugly in place and are made to stand the test of time.

Tubing

We use T304 stainless steel tubing throughout. We brush and de-burr all pipes, use mandrel bending techniques to ensure the pipes keep a constant diameter throughout, and use argon-back purged TIG welding for a strong and attractive weld.

Tunnel Brace

The factory stamped steel tunnel brace leaves little to be desired. We’ve redesigned ours to sit slightly lower in the tunnel to allow for larger exhaust tubing. As an added benefit, the CNC-bent laser-cut brace adds additional structural rigidity to the chassis!

Clamps

Our system uses OEM-style low-profile slip clamps and T304 stainless-steel Torca AccuSeal clamps for the exhaust tips. Our clamp selection allows the system to sit high in the exhaust tunnel, as is favored by lowered vehicles, with ultimate compatibility no matter what DP you may have. The clamps make for easy swapping of the exhaust tips, and slide out of the way to make adding or removing a Race DP easy. Each connection point is strategically placed to ensure the system has minimal opportunity to rotate during install or during years of heavy driving.

DP Compatibility

We’ve designed our system to be 100% bolt-on with the factory exhaust DP and APR Race DP (Please see below). 

DPK0014 - APR Cast Downpipe Exhaust System For Audi 4.0T Quattro